I have 2 quick electrical questions. 77 Leyland Mini

1. Do I need to run the third brown wire (+) from the alternator to solenoid?
The alternator charges fine but the 2mm brown wire has been cut off. I have a Lucas 14AC. Currently have the main battery cable and field connected. The spare spade terminal is marked as "AUX +".

2. What are the 2 spare white wires that run across the front?
Can't see anything on this list of white wires that would fit.

White Ignition switch or starter solenoid to ballast resistor
White Brown Oil pressure switch to warning light or gauge, or starter relay to oil pressure switch
White Blue Choke switch to choke solenoid (unfused) and/or choke to switch to warning light, or electronic ignition distributor to drive resistor
White Red Starter switch to starter solenoid or inhibitor switch or starter relay or ignition (start position) to bulb failure unit
White Purple Fuel pump no 1 or right-hand to changeover switch
White Green Fuel pump no 2 or left-hand to changeover switch
White Light green Start switch to starter interlock or oil pressure switch to fuel pump or start inhibitor switch to starter relay or solenoid
White Yellow Ballast resistor to coil or starter solenoid to coil
White Black Ignition coil contact breaker to distributor contact breaker, or distributor side of coil to voltage impulse tachometer
White Pink Ignition switch to radio fuse
White Slate Current tachometer to ignition coil
White Orange Hazard warning lead to switch

Aren't the white wires for the tacho? Goes to the coil?

Cheers Shane

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If it's not a Cooper S, the mini was designed to be modified!

Early cars with alternator like my Matic only had 1 brown wire from the alternator to the battery stud.
I'm currently running a Clubby alternator, with 1 wire and the other spade is spare. Adding a 2nd wire will send 1/2 the current output through each.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I will leave the alternator alone - i think it is a replacement so the extra brown wire may have been connected to the original alternator.
They could be tacho wires. My car had a 2 gauge cluster from new but now has a 3 guage cluster with tacho. Only thing is i already have a whit wire going to the coil and everything is already working. Doesn't really matter. I have put them back inside the loom where I found them.

There are 2 types of clubman tachos.
Early cars had a current sensing tacho which needs the 2 white wires connected in series with the coil.
Later cars had a voltage sensing tacho which only requires one wire connected to the distributor side of the coil.

RonR

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68 build Mk1 Cooper S
72 Clubman GT project. Total restoration required

Hi Ron
My car has the current sensing tacho. I have peeled back the wiring loom a bit more and found 3 white wires from the cabin. 2 are the ones going nowhere. The third one is going to my coil.
Its all taped back up now so on to the next job.

The extra brown wires are a bit of a curiosity of the time. When pushing full charge current down the relatively thin charge wire (relative to the current it is pushing out) the alternator would measure a higher voltage at the back of the alternator than at the solenoid post. Its Voltage Triangle stuff actually. 12V(Batt) + 40Amp x 0.05 = 14 volts. The figures here are inaccurate, but the maths demonstrate the problem for the regulator.

So there was a second brown voltage sense wire for the purpose of the regulator to allow it to measure the actual battery voltage rather than the artificially high voltage at the back of the alternator. Many alternators got rid of this extra requirement, but the wire often remains.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.